Add compound assignment operators

Author: pdimov

include/boost/lambda2/lambda2.hpp

@@ -127,6 +127,17 @@ BOOST_LAMBDA2_UNARY_FN(--, decrement)
 BOOST_LAMBDA2_POSTFIX_FN(++, postfix_increment)
 BOOST_LAMBDA2_POSTFIX_FN(--, postfix_decrement)
 
+BOOST_LAMBDA2_BINARY_FN(+=, plus_equal)
+BOOST_LAMBDA2_BINARY_FN(-=, minus_equal)
+BOOST_LAMBDA2_BINARY_FN(*=, multiplies_equal)
+BOOST_LAMBDA2_BINARY_FN(/=, divides_equal)
+BOOST_LAMBDA2_BINARY_FN(%=, modulus_equal)
+BOOST_LAMBDA2_BINARY_FN(&=, bit_and_equal)
+BOOST_LAMBDA2_BINARY_FN(|=, bit_or_equal)
+BOOST_LAMBDA2_BINARY_FN(^=, bit_xor_equal)
+BOOST_LAMBDA2_BINARY_FN(<<=, left_shift_equal)
+BOOST_LAMBDA2_BINARY_FN(>>=, right_shift_equal)
+
 // operators
 
 template<class T> using remove_cvref_t = std::remove_cv_t<std::remove_reference_t<T>>;
@@ -202,6 +213,19 @@ BOOST_LAMBDA2_UNARY_LAMBDA(--, lambda2_detail::decrement)
 BOOST_LAMBDA2_POSTFIX_LAMBDA(++, lambda2_detail::postfix_increment)
 BOOST_LAMBDA2_POSTFIX_LAMBDA(--, lambda2_detail::postfix_decrement)
 
+// compound assignment
+
+BOOST_LAMBDA2_BINARY_LAMBDA(+=, lambda2_detail::plus_equal)
+BOOST_LAMBDA2_BINARY_LAMBDA(-=, lambda2_detail::minus_equal)
+BOOST_LAMBDA2_BINARY_LAMBDA(*=, lambda2_detail::multiplies_equal)
+BOOST_LAMBDA2_BINARY_LAMBDA(/=, lambda2_detail::divides_equal)
+BOOST_LAMBDA2_BINARY_LAMBDA(%=, lambda2_detail::modulus_equal)
+BOOST_LAMBDA2_BINARY_LAMBDA(&=, lambda2_detail::bit_and_equal)
+BOOST_LAMBDA2_BINARY_LAMBDA(|=, lambda2_detail::bit_or_equal)
+BOOST_LAMBDA2_BINARY_LAMBDA(^=, lambda2_detail::bit_xor_equal)
+BOOST_LAMBDA2_BINARY_LAMBDA(<<=, lambda2_detail::left_shift_equal)
+BOOST_LAMBDA2_BINARY_LAMBDA(>>=, lambda2_detail::right_shift_equal)
+
 } // namespace lambda2
 } // namespace boost
 

test/Jamfile

@@ -23,3 +23,4 @@ run dereference.cpp ;
 run placeholders.cpp ;
 run increment.cpp ;
 run subscript.cpp ;
+run compound.cpp ;

test/compound.cpp

@@ -0,0 +1,32 @@
+// Copyright 2021 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/lambda2.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+#define TEST_COMPOUND(Op) \
+    BOOST_TEST_EQ( (_1 Op 1)(x1), y1 Op 1 ); \
+    BOOST_TEST_EQ( (_1 Op _2)(x1, x2), y1 Op y2 ); \
+    BOOST_TEST_EQ( ((_1 Op _2) Op _3)(x1, x2, x3), (y1 Op y2) Op y3 );
+
+int main()
+{
+    using namespace boost::lambda2;
+
+    int x1 = 1, x2 = 2, x3 = 3, y1 = 1, y2 = 2, y3 = 3;
+
+    TEST_COMPOUND(+=)
+    TEST_COMPOUND(-=)
+    TEST_COMPOUND(*=)
+    TEST_COMPOUND(/=)
+    TEST_COMPOUND(%=)
+    TEST_COMPOUND(&=)
+    TEST_COMPOUND(|=)
+    TEST_COMPOUND(^=)
+    TEST_COMPOUND(<<=)
+    TEST_COMPOUND(>>=)
+
+    return boost::report_errors();
+}